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Bio-contamination of water through biofouling, which involves the natural colonization of submerged surfaces by waterborne organisms, is a global socio-economic concern, allied to premature materials bio-corrosion and high human health risks. Most effective strategies release toxic and persistent disinfectant compounds into the aquatic medium, causing environmental problems and leading to more stringent legislation regarding their use. To minimize these side effects, a newly non-biocide-release coating strategy suitable for several polymeric matrices, namely polydimethylsiloxane and polyurethane (PU)-based coatings, was used to generate antimicrobial ceramic filters for water bio-decontamination. The best results, in terms of antimicrobial activity and biocide release, showed an expressed delay and a decrease of up to 66% in the population of methicillin-resistant Staphylococcus aureus bacteria on ceramic filters coated with polyurethane (PU)-based coatings containing grafted Econea biocide, and no evidence of biocide release after being submerged for 45 days in water. Biocidal PU-based surfaces were also less prone to Enterococcus faecalis biofilm formation under flow conditions with an average reduction of 60% after 48 h compared to a pristine PU-based surface. Biocidal coated filters show to be a potential eco-friendly alternative for minimizing the environmental risks associated with biofouling formation in water-based industrial systems., This research work was supported by national funds through FCT-Foundation for Science and Technology within the scope of research units grants to BioISI (UIDB/04046/2020 and UIDP/04046/2020), and also by Base Funding-UIDB/00511/2020 of the Laboratory for Process Engineering, Environment, Biotechnology, and Energy-LEPABE-funded by national funds through the FCT/MCTES (PIDDAC). O. Ferreira also acknowledges the Grant PD/BD/128370/2017. L.C.G. and E.R.S. thank the Portuguese Foundation for Science and Technology (FCT) for their work contracts through the Scientific Employment Stimulus-Individual Call (CEECIND/01700/2017 and CEECIND/03530/2018).

A La-Sr/CaO catalyst was studied operando during the oxidative coupling of methane (OCM) reaction using the X-ray diffraction computed tomography technique. Full-pattern Rietveld analysis was performed in order to track the evolving solid-state chemistry during the temperature ramp, OCM reaction, as well as after cooling to room temperature. We observed a uniform distribution of the catalyst main components: La2O3, CaO-SrO mixed oxide, and the high-temperature rhombohedral polymorph of SrCO3. These were stable initially in the reaction; however, doubling the gas hourly space velocity resulted in the decomposition of SrCO3 to SrO, which subsequently led to the formation of a second CaO-SrO mixed oxide. These two mixed CaO-SrO oxides differed in terms of the extent of Sr incorporation into their unit cell. By applying Vegard's law during the Rietveld refinement, it was possible to create maps showing the spatial variation of Sr occupancy in the mixed CaO-SrO oxides. The formation of the Sr-doped CaO species is expected to have an important role in this system through the enhancement of the lattice oxygen diffusion as well as increased catalyst basicity.

The present work investigates the preparation of NiCe/γ-Al2O3 coated cordierite monoliths for oxidative dehydrogenation of ethane (ODE) reaction through a two steps procedure: the primer deposition of a γ-Al2O3 coating consisting in a mixture of micro and nanoparticles via the washcoating method and the latter incorporation of the active phase by impregnation. Moreover, a modification in these two steps was made: the suppression of some calcination steps to save energy in the manufacture process. The structured catalysts, named as Ni(X)Ce(Y)-M, where X = 13 or 19 wt%. Ni and Y = 5 or 8 wt%. Ce respectively, with respect to the alumina loading, were characterized by SEM/EDX, XRD, FTIR, LRS and XPS, and their catalytic activity was tested in the ODE reaction. Furthermore, their mechanical resistance to vibration was studied. Similar results corresponding to the un-promoted system are also presented for comparison. It was found that the co-impregnation of nickel and cerium was affected by the suppression of some calcinations: a preferential absorption of Ce rather than Ni occurred, generating at the end a catalytic coating with a higher Ce/Ni ratio than that of the precursor solution and a lower Ni loading than that of Ni(13)-M. On the other side, in the NiCe-based catalysts the properties of the active sites remained the same despite the increment in the active phase, at a fixed Ce/Ni nominal atomic ratio of 0.17. In the case of the Ni(19)Ce(8)-M system, although the Ni/Al atomic ratios were found lower than those of the nominal ones by EDX and XPS and ethylene selectivity decayed, ethane conversion resulted markedly higher, leading to an improved ethylene yield. Fil: Brussino, Paula. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica ; Argentina Fil: Bortolozzi, Juan Pablo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica ; Argentina Fil: Milt, Viviana Guadalupe. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica ; Argentina Fil: Banus, Ezequiel David. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica ; Argentina Fil: Ulla, Maria Alicia del H.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica ; Argentina

Different strategies for the generation of Ni (15 wt.%)/Al2O3 catalytic coatings onto cordierite monoliths applied to the oxidative dehydrogenation of ethane (ODHE) were investigated. Strategy 1 involved the deposition of an alumina layer (nanoparticles or micro + nanoparticles) and the later incorporation of the active phase. Strategy 2 employed a suspension containing a powder catalyst that was used to deposit the catalytic film. Morphological (SEM) and physicochemical (LRS and XPS) characterizations were used to explain the catalytic performance of the structured systems. The NiO particles distribution on the catalytic coatings obtained was analyzed via SEM-EDX performed in different monolith regions. The ultrasonic test was used to evaluate the anchoring of these catalytic films to the substrates. It was concluded that the selection of both the strategy and the particle size of the support is extremely important in order to obtain a homogeneously dispersed, accessible and highly adhered to the substrate catalyst. Fil: Brussino, Paula. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica ; Argentina Fil: Bortolozzi, Juan Pablo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica ; Argentina Fil: Milt, Viviana Guadalupe. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica ; Argentina Fil: Banus, Ezequiel David. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica ; Argentina Fil: Ulla, Maria Alicia del H.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica ; Argentina

The transition toward a "Hydrogen Economy" could ensure significant advantages in terms of energetic efficiency and environmental impact, with reduced production of greenhouse gases. In the near term, considering the actual lack of infrastructure for H2 storage and distribution, equipment operating with FCs fed with H2 or H2-rich gases, produced by reforming of available fossil (Natural Gas, LPG, Diesel, etc..) and renewable (biogas, bioethanol) fuels, represent a valid and interesting alternative to actual energy generation systems. Even if the reforming technologies are mature, especially SR for hydrogen production on a large scale, more efforts are required for process intensification developing compact systems for small-scale distributed hydrogen production (50-1500 kg/day). Central issues of reforming processes for small-scale application are the development of efficient, stable and low-cost catalysts coupled with the realization of compact and lightweight, fuel processor. In this work, the performances of structured catalysts, based on Rh (1.5wt.%), supported on CeO2, coated on cordierite monoliths (400 cpsi, diameter 1 cm, length 1.5 cm) and alumina foams (20, 30, 40 PPI) were investigated and compared under Steam Reforming (SR) and Oxy Stream Reforming (OSR) of methane (CH4), n-dodecane (n-C12H26) and biogas (CH4=60%, CO2=40%). The structured supports were lined with a novel procedure combining the Solution Combustion Synthesis with the Impregnation technique. All prepared catalysts were characterized by XRD, TEM, SEM and chemisorption analyses. Both monolith and foam catalysts have shown comparable characteristics in terms of uniform thin coating (thickness between 20-30 ?m), high mechanical strength (negligible weight loss ? 0.4% on total weight of the sample after ultrasonic treatment); a low-pressure drop of the monolith respect the foam was observed. In general both foam and monolith samples have shown good catalytic performances, also at high flow rates, in terms of high fuel conversion (CH4Methane = 99-90%, CH4biogas = 99-98%, n-C12H26 = 99% for SR process and CH4Methane = 99-98%, CH4biogas = 99-96%, n-C12H26 = 99% for OSR process) and hydrogen concentration (H2methane= 76-74, H2biogas = 64-62%, H2n-C12H26 = 72-70% in dry and nitrogen-free basis for SR process and H2methane = 69-68%, H2biogas = 59-58%, H2n-C12H26 = 64-60%, in dry basis and nitrogen free for OSR process). The obtained results represent a promising advance in the process intensification of fuel reforming technology: high performances at high space velocity, together with relatively low-cost catalysts, involve a more compact, lightweight and less expensive fuel processors.

Within the Bioenergy sector, the biogas can be considered as one of the most widespread renewable fuels [1]. The utilization of biogas (CH4 and CO2 mixtures) to produce syngas/hydrogen by reforming processes to feed fuel cells for stationary (CHP) and mobile application (FCEVs), represents an alternative route to the traditional utilization of this biofuel in less efficient and polluting engines. Among the possible reforming reactions, Steam reforming (SR) is widely used for the hydrogen production process and is the largest and generally most economical especially for industrial application [2]. Another option can be represented by the Tri-Reforming (TR) process. The simultaneous occurrence of dry reforming reaction in presence of O2 and H2O, can help to overcome critical factors of the reaction, as the deactivation by coke deposition reducing at the same time the overall endothermicity of the process; moreover the CO2 contained in the biogas can be used as a reagent in operating conditions with low water and oxygen contents [3]. Even if the reforming technologies are mature, especially SR for hydrogen production on a large scale, more efforts are required for process intensification to develop compact systems for small scale distributed hydrogen production (100-500 kg/day). Central issues of reforming processes for small scale application are the development of efficient, stable and low cost catalysts and the realization of more compact and lightweight, fuel processor [4]. In this respect different catalyst configurations (foams, honeycombs, gauze, microchannels) were proposed as alternative to traditional packed-bed reactors for the realization of compact reactors. The advantages of structured catalysts are related especially to the large surface-to-volume ratio that leads to good heat and mass transfer properties and low pressure drop. In this work, the performances of structured catalysts, based on Rh (1.5wt.%), supported on CeO2, coated on cordierite monoliths (400 cpsi, diameter 1 cm, length 1.5 cm) and alumina foams (20, 30, 40 PPI, diameter 1 cm, length 1.5 cm) were investigated and compared under the biogas SR and TR condition.

CoFER and PtCoFER were prepared with different Co loadings and Co/Pt ratios. The resulting powders were washcoated on ceramic honeycombs. To increase adherence, silica was added to the slurry as a binder. The samples were assayed for the SCR of NOx with methane in excess oxygen. The maximum conversion of NOx to N2 for each formulation when plotted versus either Co loading or Co/Pt ratio presented maxima. All catalysts partially deactivated with 2% water. A thorough TPR, XPS and LRS characterization of fresh and deactivated catalysts showed that two deactivation mechanisms are operative. At low Co loadings, the formation of Pt clusters is responsible for the low selectivity, while for higher loadings Co 3O4 is formed and is the non-selective species. Fil: Boix, Alicia Viviana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; Argentina Fil: Lombardo, Eduardo Agustin. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; Argentina Fil: Miro, Eduardo Ernesto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; Argentina

Structured catalysts were prepared, characterized and evaluated in NO3 - removal from drinking water. Different suspensions containing a previously optimized PdCu/5wt% ZrO2-Al2O3 powder catalyst (hereinafter PdCu/5ZAp) were prepared and deposited on cordierite monoliths by washcoating. The effect of suspension concentration, the particle size, the immersion number, the use of suspension stabilizer agent, and an alumina precoating on the coating adherence and catalytic performance were studied. All the prepared structured catalysts were active for the elimination of NO3 - and presented good selectivity to N2 (> 93%) in synthetic water samples. The catalyst performance was related to the amount of deposited catalyst. The highest activity and the best coating adherence were obtained with the structured catalyst prepared by a single immersion in a 14 wt% concentration suspension, which was obtained from the powder catalyst milled for 10 h and stabilized with colloidal alumina. This catalyst also showed good activity when it was reused for four cycles and when it was evaluated with real water samples., Facultad de Ciencias Exactas, Facultad de Ingeniería

Δημοσίευση σε επιστημονικό περιοδικό Summarization: The N2O decomposition and reduction by CO or C3H6 over rare earth oxides (REOs)-modified Pt/Al2O3 structured catalysts, i.e., coated on ceramic honeycomb monoliths, were comparatively investigated in a wide temperature interval of 100–600 °C, either in the presence or in the absence of excess O2 and H2O. It was shown that the de-N2O efficiency can be remarkably enhanced via modification of Al2O3 support with rare earth oxides (REOs). In specific, complete conversion of N2O can be attained over REOs-modified catalysts at a relatively low temperature (ca. 480 °C) even in the presence of excess O2, which in general depresses de-N2O efficiency, in opposite to the unmodified Pt/Al2O3 catalyst, over which, 20% N2O conversion is never exceeded for temperatures up to 600 °C. In terms of turnover frequency (TOF), optimally modified (by REOs) Pt–Al2O3 catalyst exhibits one order of magnitude higher activity compared to that of the unpromoted Pt/Al2O3 sample. Under reducing conditions the N2O conversion is strongly enhanced by C3H6 and especially by CO, whereas marginal inhibition is induced by reducing agents under excess oxygen conditions. Water was found to induce a detrimental influence on N2O decomposition, with its effect however, to be partially reversible. An in situ diffuse reflectance infrared Fourier transform spectroscopic (DRIFTS) study, using CO as a probe molecule, was performed over both unmodified and REOs-modified Pt/Al2O3 catalysts to correlate their surface characteristics with their de-N2O efficacy. The results revealed that the superior catalytic performance of promoted samples could be mainly attributed to the increase of Pt dispersion as well as to the development of Pt sites with exceptional electron density, located on the metal–support interfacial area. Παρουσιάστηκε στο: Applied Catalysis B: Environmental